diff --git a/.github/workflows/test_and_lint.yml b/.github/workflows/test_and_lint.yml
index 6a0f8d16..2720847c 100644
--- a/.github/workflows/test_and_lint.yml
+++ b/.github/workflows/test_and_lint.yml
@@ -19,7 +19,7 @@ jobs:
       - name: Install Go
         uses: actions/setup-go@v5
         with:
-          go-version: '1.19'
+          go-version: '1.20'
           cache: false
       - run: go get
       - run: go generate ./...
@@ -34,7 +34,7 @@ jobs:
         uses: actions/setup-go@v5
         with:
           cache: false
-          go-version: '1.19'
+          go-version: '1.20'
       - run: go get
       - run: go generate ./...
       - name: Go vet
diff --git a/.gitignore b/.gitignore
index 8b01fd6b..5041f303 100644
--- a/.gitignore
+++ b/.gitignore
@@ -103,3 +103,6 @@ fabric.properties
 # Go workspace file
 go.work
 
+# Running stub
+sig.bin
+qrcode.png
diff --git a/client/client.go b/client/client.go
index 4bb549eb..f92e6fff 100644
--- a/client/client.go
+++ b/client/client.go
@@ -12,6 +12,7 @@ import (
 
 	"github.com/LagrangeDev/LagrangeGo/packets/tlv"
 
+	"github.com/LagrangeDev/LagrangeGo/utils/binary"
 	binary2 "github.com/LagrangeDev/LagrangeGo/utils/binary"
 
 	"github.com/LagrangeDev/LagrangeGo/utils"
@@ -81,11 +82,11 @@ func (c *QQClient) Login(password, qrcodePath string) (bool, error) {
 }
 
 func (c *QQClient) FecthQrcode() ([]byte, string, error) {
-	body := utils.NewPacketBuilder(nil).
+	body := binary2.NewBuilder(nil).
 		WriteU16(0).
 		WriteU64(0).
 		WriteU8(0).
-		WriteTlv([][]byte{
+		WritePacketTlv(
 			tlv.T16(c.appInfo.AppID, c.appInfo.SubAppID,
 				utils.MustParseHexStr(c.deviceInfo.Guid), c.appInfo.PTVersion, c.appInfo.PackageName),
 			tlv.T1b(),
@@ -94,7 +95,7 @@ func (c *QQClient) FecthQrcode() ([]byte, string, error) {
 			tlv.T35(c.appInfo.PTOSVersion),
 			tlv.T66(c.appInfo.PTOSVersion),
 			tlv.Td1(c.appInfo.OS, c.deviceInfo.DeviceName),
-		}).WriteU8(3).Pack(-1)
+		).WriteU8(3).Pack(binary.PackTypeNone)
 
 	packet := wtlogin.BuildCode2dPacket(c.Uin, 0x31, c.appInfo, body)
 	response, err := c.SendUniPacketAndAwait("wtlogin.trans_emp", packet)
@@ -114,7 +115,7 @@ func (c *QQClient) FecthQrcode() ([]byte, string, error) {
 		// 这样是不对的，调试后发现应该丢一个字节，然后读下一个字节才是数据的大小
 		// string(binary2.NewReader(tlvs[209]).ReadBytesWithLength("u16", true))
 		urlreader.ReadU8()
-		return tlvs[0x17], string(urlreader.ReadBytesWithLength("u8", false)), nil
+		return tlvs[0x17], utils.B2S(urlreader.ReadBytesWithLength("u8", false)), nil
 	}
 
 	return nil, "", fmt.Errorf("err qr retcode %d", retCode)
@@ -126,12 +127,12 @@ func (c *QQClient) GetQrcodeResult() (qrcodeState.State, error) {
 		return -1, errors.New("no qrsig found, execute fetch_qrcode first")
 	}
 
-	body := utils.NewPacketBuilder(nil).
-		WriteBytes(c.sig.Qrsig, "u16", false).
+	body := binary2.NewBuilder(nil).
+		WritePacketBytes(c.sig.Qrsig, "u16", false).
 		WriteU64(0).
 		WriteU32(0).
 		WriteU8(0).
-		WriteU8(0x83).Pack(-1)
+		WriteU8(0x83).Pack(binary.PackTypeNone)
 
 	response, err := c.SendUniPacketAndAwait("wtlogin.trans_emp",
 		wtlogin.BuildCode2dPacket(0, 0x12, c.appInfo, body))
@@ -172,7 +173,7 @@ func (c *QQClient) KeyExchange() {
 }
 
 func (c *QQClient) PasswordLogin(password string) (loginState.State, error) {
-	md5Password := utils.MD5Digest([]byte(password))
+	md5Password := utils.MD5Digest(utils.S2B(password))
 
 	cr := tlv.T106(
 		c.appInfo.AppID,
@@ -226,25 +227,25 @@ func (c *QQClient) QrcodeLogin(refreshInterval int) (bool, error) {
 
 	app := c.appInfo
 	device := c.deviceInfo
-	body := utils.NewPacketBuilder(nil).
+	body := binary2.NewBuilder(nil).
 		WriteU16(0x09).
-		WriteTlv([][]byte{
-			utils.NewPacketBuilder(nil).WriteBytes(c.t106, "", true).Pack(0x106),
+		WritePacketTlv(
+			binary2.NewBuilder(nil).WritePacketBytes(c.t106, "", true).Pack(0x106),
 			tlv.T144(c.sig.Tgtgt, app, device),
 			tlv.T116(app.SubSigmap),
 			tlv.T142(app.PackageName, 0),
 			tlv.T145(utils.MustParseHexStr(device.Guid)),
 			tlv.T18(0, app.AppClientVersion, int(c.Uin), 0, 5, 0),
-			tlv.T141([]byte("Unknown"), make([]byte, 0)),
+			tlv.T141([]byte("Unknown"), nil),
 			tlv.T177(app.WTLoginSDK, 0),
 			tlv.T191(0),
 			tlv.T100(5, app.AppID, app.SubAppID, 8001, app.MainSigmap, 0),
 			tlv.T107(1, 0x0d, 0, 1),
-			tlv.T318(make([]byte, 0)),
-			utils.NewPacketBuilder(nil).WriteBytes(c.t16a, "", true).Pack(0x16a),
+			tlv.T318(nil),
+			binary2.NewBuilder(nil).WritePacketBytes(c.t16a, "", true).Pack(0x16a),
 			tlv.T166(5),
 			tlv.T521(0x13, "basicim"),
-		}).Pack(-1)
+		).Pack(binary.PackTypeNone)
 
 	response, err := c.SendUniPacketAndAwait(
 		"wtlogin.login",
diff --git a/client/listener.go b/client/listener.go
index 73662750..a185410a 100644
--- a/client/listener.go
+++ b/client/listener.go
@@ -10,6 +10,7 @@ import (
 	msgConverter "github.com/LagrangeDev/LagrangeGo/message"
 	"github.com/LagrangeDev/LagrangeGo/packets/pb/message"
 	"github.com/LagrangeDev/LagrangeGo/packets/wtlogin"
+	"github.com/LagrangeDev/LagrangeGo/utils"
 	"github.com/LagrangeDev/LagrangeGo/utils/binary"
 )
 
@@ -63,7 +64,7 @@ func decodeOlPushServicePacket(c *QQClient, pkt *wtlogin.SSOPacket) (any, error)
 			if err != nil {
 				return nil, err
 			}
-			pb.Operator = []byte(Operator.OperatorField1.OperatorUid)
+			pb.Operator = utils.S2B(Operator.OperatorField1.OperatorUid)
 		}
 		return eventConverter.ParseMemberDecreaseEvent(&pb), nil
 	case 84: // group request join notice
diff --git a/event/group.go b/event/group.go
index cbc16095..28249253 100644
--- a/event/group.go
+++ b/event/group.go
@@ -2,6 +2,7 @@ package event
 
 import (
 	"github.com/LagrangeDev/LagrangeGo/packets/pb/message"
+	"github.com/LagrangeDev/LagrangeGo/utils"
 )
 
 type (
@@ -96,7 +97,7 @@ func ParseMemberIncreaseEvent(event *message.GroupChange) *GroupMemberIncrease {
 			GroupUin: event.GroupUin,
 		},
 		MemberUid:  event.MemberUid,
-		InvitorUid: string(event.Operator),
+		InvitorUid: utils.B2S(event.Operator),
 		JoinType:   event.IncreaseType,
 	}
 }
@@ -107,7 +108,7 @@ func ParseMemberDecreaseEvent(event *message.GroupChange) *GroupMemberDecrease {
 			GroupUin: event.GroupUin,
 		},
 		MemberUid:   event.MemberUid,
-		OperatorUid: string(event.Operator),
+		OperatorUid: utils.B2S(event.Operator),
 		ExitType:    event.DecreaseType,
 	}
 }
diff --git a/go.mod b/go.mod
index 4b4f965d..19f8b114 100644
--- a/go.mod
+++ b/go.mod
@@ -1,6 +1,6 @@
 module github.com/LagrangeDev/LagrangeGo
 
-go 1.19
+go 1.20
 
 require (
 	github.com/RomiChan/protobuf v0.1.1-0.20230204044148-2ed269a2e54d
diff --git a/info/device.go b/info/device.go
index f8d3d2b7..21311adf 100644
--- a/info/device.go
+++ b/info/device.go
@@ -18,8 +18,8 @@ type DeviceInfo struct {
 
 func NewDeviceInfo(uin int) *DeviceInfo {
 	return &DeviceInfo{
-		Guid:          fmt.Sprintf("%X", utils.MD5Digest([]byte(strconv.Itoa(uin)))),
-		DeviceName:    fmt.Sprintf("Lagrange-%X", utils.MD5Digest([]byte(strconv.Itoa(uin)))[0:4]),
+		Guid:          fmt.Sprintf("%X", utils.MD5Digest(utils.S2B(strconv.Itoa(uin)))),
+		DeviceName:    fmt.Sprintf("Lagrange-%X", utils.MD5Digest(utils.S2B(strconv.Itoa(uin)))[0:4]),
 		SystemKernel:  fmt.Sprintf("%s %s", platform.GetSystem(), platform.GetVersion()),
 		KernelVersion: platform.GetVersion(),
 	}
diff --git a/info/serialize.go b/info/serialize.go
index 74e7eb95..928a4c62 100644
--- a/info/serialize.go
+++ b/info/serialize.go
@@ -27,7 +27,7 @@ func Encode(sig *SigInfo) []byte {
 	return binary.NewBuilder(nil).
 		WriteBytes(dataHash, true).
 		WriteBytes(buffer.Bytes(), true).
-		Pack(-1)
+		Pack(binary.PackTypeNone)
 }
 
 func Decode(buf []byte, verify bool) *SigInfo {
@@ -35,7 +35,7 @@ func Decode(buf []byte, verify bool) *SigInfo {
 	dataHash := reader.ReadBytesWithLength("u16", false)
 	data := reader.ReadBytesWithLength("u16", false)
 
-	if verify && string(dataHash) != string(utils.MD5Digest(data)) {
+	if verify && !bytes.Equal(dataHash, utils.MD5Digest(data)) {
 		panic("Data hash does not match")
 	}
 	buffer := bytes.NewBuffer(data)
diff --git a/info/sig.go b/info/sig.go
index bb0f7693..30ea213d 100644
--- a/info/sig.go
+++ b/info/sig.go
@@ -23,18 +23,7 @@ type SigInfo struct {
 
 func NewSigInfo(seq int) *SigInfo {
 	return &SigInfo{
-		Uid:         "",
-		Sequence:    seq,
-		Tgtgt:       make([]byte, 0),
-		Tgt:         make([]byte, 0),
-		D2:          make([]byte, 0),
-		D2Key:       make([]byte, 16),
-		Qrsig:       make([]byte, 0),
-		ExchangeKey: make([]byte, 0),
-		KeySig:      make([]byte, 0),
-		Cookies:     "",
-		UnusualSig:  make([]byte, 0),
-		TempPwd:     make([]byte, 0),
-		CaptchaInfo: [3]string{"", "", ""},
+		Sequence: seq,
+		D2Key:    make([]byte, 16),
 	}
 }
diff --git a/main.go b/main.go
index 81f749c1..997aee2d 100644
--- a/main.go
+++ b/main.go
@@ -3,11 +3,11 @@ package main
 
 import (
 	"fmt"
-	"github.com/LagrangeDev/LagrangeGo/message"
 	"os"
 
 	"github.com/LagrangeDev/LagrangeGo/client"
 	"github.com/LagrangeDev/LagrangeGo/info"
+	"github.com/LagrangeDev/LagrangeGo/message"
 )
 
 func main() {
@@ -23,7 +23,7 @@ func main() {
 
 	qqclient.GroupMessageEvent.Subscribe(func(client *client.QQClient, event *message.GroupMessage) {
 		if event.ToString() == "114514" {
-			img, _ := os.ReadFile("/Users/wenxuanlin/Desktop/2373259535.png")
+			img, _ := os.ReadFile("./testgroup.png")
 			_, err := client.SendGroupMessage(event.GroupCode, []message.IMessageElement{&message.GroupImageElement{Stream: img}})
 			if err != nil {
 				return
@@ -32,7 +32,7 @@ func main() {
 	})
 
 	qqclient.PrivateMessageEvent.Subscribe(func(client *client.QQClient, event *message.PrivateMessage) {
-		img, _ := os.ReadFile("/Users/wenxuanlin/Desktop/2373259535.png")
+		img, _ := os.ReadFile("testprivate.png")
 		_, err := client.SendPrivateMessage(event.Sender.Uin, []message.IMessageElement{&message.FriendImageElement{Stream: img}})
 		if err != nil {
 			return
diff --git a/message/message.go b/message/message.go
index 8c41b267..758fc332 100644
--- a/message/message.go
+++ b/message/message.go
@@ -8,6 +8,7 @@ import (
 	"strings"
 
 	"github.com/LagrangeDev/LagrangeGo/packets/pb/message"
+	"github.com/LagrangeDev/LagrangeGo/utils"
 	"github.com/LagrangeDev/LagrangeGo/utils/binary"
 	"github.com/LagrangeDev/LagrangeGo/utils/proto"
 )
@@ -195,7 +196,7 @@ func parseMessageElements(msg []*message.Elem) []IMessageElement {
 			return []IMessageElement{
 				&ShortVideoElement{
 					Name:      elem.VideoFile.FileName,
-					Uuid:      []byte(elem.VideoFile.FileUuid),
+					Uuid:      utils.S2B(elem.VideoFile.FileUuid),
 					Size:      elem.VideoFile.FileSize,
 					ThumbSize: elem.VideoFile.ThumbFileSize,
 					Md5:       elem.VideoFile.FileMd5,
diff --git a/packets/tlv/common.go b/packets/tlv/common.go
index fe1b1664..263ef9a1 100644
--- a/packets/tlv/common.go
+++ b/packets/tlv/common.go
@@ -5,12 +5,13 @@ import (
 
 	"github.com/LagrangeDev/LagrangeGo/info"
 	"github.com/LagrangeDev/LagrangeGo/utils"
+	"github.com/LagrangeDev/LagrangeGo/utils/binary"
 	"github.com/LagrangeDev/LagrangeGo/utils/crypto"
 )
 
 // T18 默认参数 pingVersion, unknown = 0, ssoVersion = 5
 func T18(appID, appClientVersion, uin, pingVersion, ssoVersion, unknown int) []byte {
-	return utils.NewPacketBuilder(nil).
+	return binary.NewBuilder(nil).
 		WriteU16(uint16(pingVersion)).
 		WriteU32(uint32(ssoVersion)).
 		WriteU32(uint32(appID)).
@@ -22,7 +23,7 @@ func T18(appID, appClientVersion, uin, pingVersion, ssoVersion, unknown int) []b
 
 // T100 dbBufVer 默认为 0
 func T100(ssoVersion, appID, subAppID, appClientVersion, sigmap, dbBufVer int) []byte {
-	return utils.NewPacketBuilder(nil).
+	return binary.NewBuilder(nil).
 		WriteU16(uint16(dbBufVer)).
 		WriteU32(uint32(ssoVersion)).
 		WriteU32(uint32(appID)).
@@ -36,9 +37,9 @@ func T100(ssoVersion, appID, subAppID, appClientVersion, sigmap, dbBufVer int) [
 func T106(appId, appClientVersion, uin int, guid string, passwordMd5, tgtgtKey, ip []byte, savePassword bool) []byte {
 	// password_md5 + bytes(4) + write_u32(uin).pack()
 	key := utils.MD5Digest(append(passwordMd5, append(make([]byte, 4),
-		utils.NewPacketBuilder(nil).WriteU32(uint32(uin)).Pack(-1)...)...))
+		binary.NewBuilder(nil).WriteU32(uint32(uin)).Pack(binary.PackTypeNone)...)...))
 
-	body := utils.NewPacketBuilder(nil).
+	body := binary.NewBuilder(nil).
 		WriteStruct(uint16(4), //  tgtgt version
 			utils.RandU32(),
 			uint32(0), // sso_version, depreciated
@@ -46,26 +47,26 @@ func T106(appId, appClientVersion, uin int, guid string, passwordMd5, tgtgtKey,
 			uint32(appClientVersion),
 			uint64(uin)).
 		WriteU32(uint32(utils.TimeStamp())).
-		WriteBytes(ip, "", true).
+		WritePacketBytes(ip, "", true).
 		WriteBool(savePassword).
-		WriteBytes(passwordMd5, "", true).
-		WriteBytes(tgtgtKey, "", true).
+		WritePacketBytes(passwordMd5, "", true).
+		WritePacketBytes(tgtgtKey, "", true).
 		WriteU32(0).
 		WriteBool(true).
-		WriteBytes(utils.MustParseHexStr(guid), "", true).
+		WritePacketBytes(utils.MustParseHexStr(guid), "", true).
 		WriteU32(0).
 		WriteU32(1).
-		WriteString(strconv.Itoa(uin), "u16", false).
-		Pack(-1)
+		WritePacketString(strconv.Itoa(uin), "u16", false).
+		Pack(binary.PackTypeNone)
 
-	return utils.NewPacketBuilder(nil).
-		WriteBytes(crypto.NewTeaCipher(key).Encrypt(body), "u32", true).
+	return binary.NewBuilder(nil).
+		WritePacketBytes(crypto.NewTeaCipher(key).Encrypt(body), "u32", true).
 		Pack(0x106)
 }
 
 // T107 默认参数为 1, 0x0d, 0, 1
 func T107(picType, capType, picSize, retType int) []byte {
-	return utils.NewPacketBuilder(nil).
+	return binary.NewBuilder(nil).
 		WriteU16(uint16(picType)).
 		WriteU8(uint8(capType)).
 		WriteU16(uint16(picSize)).
@@ -74,7 +75,7 @@ func T107(picType, capType, picSize, retType int) []byte {
 }
 
 func T116(subSigmap int) []byte {
-	return utils.NewPacketBuilder(nil).
+	return binary.NewBuilder(nil).
 		WriteU8(0).
 		WriteU32(12058620). // unknown?
 		WriteU32(uint32(subSigmap)).
@@ -83,110 +84,110 @@ func T116(subSigmap int) []byte {
 }
 
 func T124() []byte {
-	return utils.NewPacketBuilder(nil).
-		WriteBytes(make([]byte, 12), "", true).
+	return binary.NewBuilder(nil).
+		WritePacketBytes(make([]byte, 12), "", true).
 		Pack(0x124)
 }
 
 func T128(appInfoOS string, deviceGuid []byte) []byte {
-	return utils.NewPacketBuilder(nil).
+	return binary.NewBuilder(nil).
 		WriteU16(0).
 		WriteU8(0).
 		WriteU8(1).
 		WriteU8(0).
 		WriteU32(0).
-		WriteString(appInfoOS, "u16", false).
-		WriteBytes(deviceGuid, "u16", false).
-		WriteString("", "u16", false).
+		WritePacketString(appInfoOS, "u16", false).
+		WritePacketBytes(deviceGuid, "u16", false).
+		WritePacketString("", "u16", false).
 		Pack(0x128)
 }
 
 // T141 默认参数 apn = []byte{0}
 func T141(simInfo, apn []byte) []byte {
-	return utils.NewPacketBuilder(nil).
-		WriteBytes(simInfo, "u32", false).
-		WriteBytes(apn, "u32", false).
+	return binary.NewBuilder(nil).
+		WritePacketBytes(simInfo, "u32", false).
+		WritePacketBytes(apn, "u32", false).
 		Pack(0x141)
 }
 
 // T142 默认参数 version = 0 注意apkID长度要过32
 func T142(apkID string, version int) []byte {
-	return utils.NewPacketBuilder(nil).
+	return binary.NewBuilder(nil).
 		WriteU16(uint16(version)).
-		// WriteString(apkID[:32], "u16", false).
+		// WritePacketString(apkID[:32], "u16", false).
 		// apkID长度没有32，不动了
-		WriteString(apkID, "u16", false).
+		WritePacketString(apkID, "u16", false).
 		Pack(0x142)
 }
 
 func T144(tgtgtKey []byte, appInfo *info.AppInfo, device *info.DeviceInfo) []byte {
-	return utils.NewPacketBuilder(tgtgtKey).
-		WriteTlv([][]byte{
+	return binary.NewBuilder(tgtgtKey).
+		WritePacketTlv(
 			T16e(device.DeviceName),
 			T147(appInfo.AppID, appInfo.PTVersion, appInfo.PackageName),
 			T128(appInfo.OS, utils.MustParseHexStr(device.Guid)),
 			T124(),
-		}).Pack(0x144)
+		).Pack(0x144)
 }
 
 func T145(guid []byte) []byte {
-	return utils.NewPacketBuilder(nil).
-		WriteBytes(guid, "", true).
+	return binary.NewBuilder(nil).
+		WritePacketBytes(guid, "", true).
 		Pack(0x145)
 }
 
 func T147(appId int, ptVersion string, packageName string) []byte {
-	return utils.NewPacketBuilder(nil).
+	return binary.NewBuilder(nil).
 		WriteU32(uint32(appId)).
-		WriteString(ptVersion, "u16", false).
-		WriteString(packageName, "u16", false).
+		WritePacketString(ptVersion, "u16", false).
+		WritePacketString(packageName, "u16", false).
 		Pack(0x147)
 }
 
 func T166(imageType int) []byte {
-	return utils.NewPacketBuilder(nil).
+	return binary.NewBuilder(nil).
 		WriteI8(int8(imageType)).
 		Pack(0x166)
 }
 
 func T16a(noPicSig []byte) []byte {
-	return utils.NewPacketBuilder(nil).
-		WriteBytes(noPicSig, "", true).
+	return binary.NewBuilder(nil).
+		WritePacketBytes(noPicSig, "", true).
 		Pack(0x16a)
 }
 
 func T16e(deviceName string) []byte {
-	return utils.NewPacketBuilder(nil).
-		WriteBytes([]byte(deviceName), "", true).
+	return binary.NewBuilder(nil).
+		WritePacketBytes(utils.S2B(deviceName), "", true).
 		Pack(0x16e)
 }
 
 // T177 默认参数 buildTime=0
 func T177(sdkVersion string, buildTime int) []byte {
-	return utils.NewPacketBuilder(nil).
+	return binary.NewBuilder(nil).
 		WriteStruct(uint8(1), uint32(buildTime)).
-		WriteString(sdkVersion, "u16", false).
+		WritePacketString(sdkVersion, "u16", false).
 		Pack(0x177)
 }
 
 // T191 默认参数 canWebVerify=0
 func T191(canWebVerify int) []byte {
-	return utils.NewPacketBuilder(nil).
+	return binary.NewBuilder(nil).
 		WriteU8(uint8(canWebVerify)).
 		Pack(0x191)
 }
 
 // T318 默认参数 tgtQr = []byte{0}
 func T318(tgtQr []byte) []byte {
-	return utils.NewPacketBuilder(nil).
-		WriteBytes(tgtQr, "", true).
+	return binary.NewBuilder(nil).
+		WritePacketBytes(tgtQr, "", true).
 		Pack(0x318)
 }
 
 // T521 默认参数 0x13, "basicim"
 func T521(productType int, productDesc string) []byte {
-	return utils.NewPacketBuilder(nil).
+	return binary.NewBuilder(nil).
 		WriteU32(uint32(productType)).
-		WriteString(productDesc, "u16", false).
+		WritePacketString(productDesc, "u16", false).
 		Pack(0x521)
 }
diff --git a/packets/tlv/qrcode.go b/packets/tlv/qrcode.go
index b1193368..aedfce50 100644
--- a/packets/tlv/qrcode.go
+++ b/packets/tlv/qrcode.go
@@ -1,36 +1,36 @@
 package tlv
 
 import (
-	"github.com/LagrangeDev/LagrangeGo/utils"
+	"github.com/LagrangeDev/LagrangeGo/utils/binary"
 	"github.com/LagrangeDev/LagrangeGo/utils/proto"
 )
 
 func T11(unusualSign []byte) []byte {
-	return utils.NewPacketBuilder(nil).
-		WriteBytes(unusualSign, "", true).
+	return binary.NewBuilder(nil).
+		WritePacketBytes(unusualSign, "", true).
 		Pack(0x11)
 }
 
 func T16(appid, subAppid int, guid []byte, ptVersion, packageName string) []byte {
-	return utils.NewPacketBuilder(nil).
+	return binary.NewBuilder(nil).
 		WriteU32(0).
 		WriteU32(uint32(appid)).
 		WriteU32(uint32(subAppid)).
-		WriteBytes(guid, "", true).
-		WriteString(packageName, "u16", false).
-		WriteString(ptVersion, "u16", false).
-		WriteString(packageName, "u16", false).
+		WritePacketBytes(guid, "", true).
+		WritePacketString(packageName, "u16", false).
+		WritePacketString(ptVersion, "u16", false).
+		WritePacketString(packageName, "u16", false).
 		Pack(0x16)
 }
 
 func T1b() []byte {
-	return utils.NewPacketBuilder(nil).
+	return binary.NewBuilder(nil).
 		WriteStruct(uint32(0), uint32(0), uint32(3), uint32(4), uint32(72), uint32(2), uint32(2), uint16(0)).
 		Pack(0x1B)
 }
 
 func T1d(miscBitmap int) []byte {
-	return utils.NewPacketBuilder(nil).
+	return binary.NewBuilder(nil).
 		WriteU8(1).
 		WriteU32(uint32(miscBitmap)).
 		WriteU32(0).
@@ -39,20 +39,20 @@ func T1d(miscBitmap int) []byte {
 }
 
 func T33(guid []byte) []byte {
-	return utils.NewPacketBuilder(nil).WriteBytes(guid, "", true).Pack(0x33)
+	return binary.NewBuilder(nil).WritePacketBytes(guid, "", true).Pack(0x33)
 }
 
 func T35(PtOSVersion int) []byte {
-	return utils.NewPacketBuilder(nil).WriteU32(uint32(PtOSVersion)).Pack(0x35)
+	return binary.NewBuilder(nil).WriteU32(uint32(PtOSVersion)).Pack(0x35)
 }
 
 func T66(PtOSVersion int) []byte {
-	return utils.NewPacketBuilder(nil).WriteU32(uint32(PtOSVersion)).Pack(0x66)
+	return binary.NewBuilder(nil).WriteU32(uint32(PtOSVersion)).Pack(0x66)
 }
 
 func Td1(AppOS, DeviceName string) []byte {
-	return utils.NewPacketBuilder(nil).
-		WriteBytes(proto.DynamicMessage{
+	return binary.NewBuilder(nil).
+		WritePacketBytes(proto.DynamicMessage{
 			1: proto.DynamicMessage{
 				1: AppOS,
 				2: DeviceName,
diff --git a/packets/wtlogin/exchange.go b/packets/wtlogin/exchange.go
index 8f9a034b..9fcfb979 100644
--- a/packets/wtlogin/exchange.go
+++ b/packets/wtlogin/exchange.go
@@ -30,7 +30,7 @@ func BuildKexExchangeRequest(uin uint32, guid string) []byte {
 		WriteBytes(encl, false).
 		WriteU32(0).
 		WriteU32(uint32(utils.TimeStamp())).
-		Pack(-1)
+		Pack(binary.PackTypeNone)
 
 	p2Hash := utils.SHA256Digest(p2)
 	encP2Hash := crypto.AesGCMEncrypt(p2Hash, encKey)
diff --git a/packets/wtlogin/oicq.go b/packets/wtlogin/oicq.go
index 67638472..b22f7dcc 100644
--- a/packets/wtlogin/oicq.go
+++ b/packets/wtlogin/oicq.go
@@ -25,23 +25,23 @@ func BuildCode2dPacket(uin uint32, cmdID int, appInfo *info.AppInfo, body []byte
 		uin,
 		"wtlogin.trans_emp",
 		appInfo,
-		utils.NewPacketBuilder(nil).
+		binary.NewBuilder(nil).
 			WriteU8(0).
 			WriteU16(uint16(len(body))+53).
 			WriteU32(uint32(appInfo.AppID)).
 			WriteU32(0x72).
-			WriteBytes(make([]byte, 3), "", true).
+			WritePacketBytes(make([]byte, 3), "", true).
 			WriteU32(uint32(utils.TimeStamp())).
 			WriteU8(2).
 			WriteU16(uint16(len(body)+49)).
 			WriteU16(uint16(cmdID)).
-			WriteBytes(make([]byte, 21), "", true).
+			WritePacketBytes(make([]byte, 21), "", true).
 			WriteU8(3).
 			WriteU32(50).
-			WriteBytes(make([]byte, 14), "", true).
+			WritePacketBytes(make([]byte, 14), "", true).
 			WriteU32(uint32(appInfo.AppID)).
-			WriteBytes(body, "", true).
-			Pack(-1),
+			WritePacketBytes(body, "", true).
+			Pack(binary.PackTypeNone),
 	)
 }
 
@@ -55,7 +55,7 @@ func BuildLoginPacket(uin uint32, cmd string, appinfo *info.AppInfo, body []byte
 		_cmd = 2066
 	}
 
-	frameBody := utils.NewPacketBuilder(nil).
+	frameBody := binary.NewBuilder(nil).
 		WriteU16(8001).
 		WriteU16(_cmd).
 		WriteU16(0).
@@ -69,19 +69,19 @@ func BuildLoginPacket(uin uint32, cmd string, appinfo *info.AppInfo, body []byte
 		WriteU32(0).
 		WriteU8(1).
 		WriteU8(1).
-		WriteBytes(make([]byte, 16), "", true).
+		WritePacketBytes(make([]byte, 16), "", true).
 		WriteU16(0x102).
 		WriteU16(uint16(len(ecdh.ECDH["secp192k1"].GetPublicKey()))).
-		WriteBytes(ecdh.ECDH["secp192k1"].GetPublicKey(), "", true).
-		WriteBytes(encBody, "", true).
+		WritePacketBytes(ecdh.ECDH["secp192k1"].GetPublicKey(), "", true).
+		WritePacketBytes(encBody, "", true).
 		WriteU8(3).
-		Pack(-1)
+		Pack(binary.PackTypeNone)
 
-	frame := utils.NewPacketBuilder(nil).
+	frame := binary.NewBuilder(nil).
 		WriteU8(2).
 		WriteU16(uint16(len(frameBody))+3). // + 2 + 1
-		WriteBytes(frameBody, "", true).
-		Pack(-1)
+		WritePacketBytes(frameBody, "", true).
+		Pack(binary.PackTypeNone)
 
 	return frame
 }
@@ -104,24 +104,24 @@ func BuildUniPacket(uin, seq int, cmd string, sign map[string]string,
 		}
 	}
 
-	ssoHeader := utils.NewPacketBuilder(nil).
+	ssoHeader := binary.NewBuilder(nil).
 		WriteU32(uint32(seq)).
 		WriteU32(uint32(appInfo.SubAppID)).
-		WriteU32(2052).                                                  // locate id
-		WriteBytes(append([]byte{0x02}, make([]byte, 11)...), "", true). //020000000000000000000000
-		WriteBytes(sigInfo.Tgt, "u32", true).
-		WriteString(cmd, "u32", true).
-		WriteBytes(make([]byte, 0), "u32", true).
-		WriteBytes(utils.MustParseHexStr(deviceInfo.Guid), "u32", true).
-		WriteBytes(make([]byte, 0), "u32", true).
-		WriteString(appInfo.CurrentVersion, "u16", true).
-		WriteBytes(head.Encode(), "u32", true).
-		Pack(-1)
-
-	ssoPacket := utils.NewPacketBuilder(nil).
-		WriteBytes(ssoHeader, "u32", true).
-		WriteBytes(body, "u32", true).
-		Pack(-1)
+		WriteU32(2052).                                                        // locate id
+		WritePacketBytes(append([]byte{0x02}, make([]byte, 11)...), "", true). //020000000000000000000000
+		WritePacketBytes(sigInfo.Tgt, "u32", true).
+		WritePacketString(cmd, "u32", true).
+		WritePacketBytes(nil, "u32", true).
+		WritePacketBytes(utils.MustParseHexStr(deviceInfo.Guid), "u32", true).
+		WritePacketBytes(nil, "u32", true).
+		WritePacketString(appInfo.CurrentVersion, "u16", true).
+		WritePacketBytes(head.Encode(), "u32", true).
+		Pack(binary.PackTypeNone)
+
+	ssoPacket := binary.NewBuilder(nil).
+		WritePacketBytes(ssoHeader, "u32", true).
+		WritePacketBytes(body, "u32", true).
+		Pack(binary.PackTypeNone)
 
 	encrypted := crypto.NewTeaCipher(sigInfo.D2Key).Encrypt(ssoPacket)
 
@@ -132,16 +132,16 @@ func BuildUniPacket(uin, seq int, cmd string, sign map[string]string,
 		_s = 1
 	}
 
-	service := utils.NewPacketBuilder(nil).
+	service := binary.NewBuilder(nil).
 		WriteU32(12).
 		WriteU8(_s).
-		WriteBytes(sigInfo.D2, "u32", true).
+		WritePacketBytes(sigInfo.D2, "u32", true).
 		WriteU8(0).
-		WriteString(strconv.Itoa(uin), "u32", true).
-		WriteBytes(encrypted, "", true).
-		Pack(-1)
+		WritePacketString(strconv.Itoa(uin), "u32", true).
+		WritePacketBytes(encrypted, "", true).
+		Pack(binary.PackTypeNone)
 
-	return utils.NewPacketBuilder(nil).WriteBytes(service, "u32", true).Pack(-1)
+	return binary.NewBuilder(nil).WritePacketBytes(service, "u32", true).Pack(binary.PackTypeNone)
 }
 
 func DecodeLoginResponse(buf []byte, sig *info.SigInfo) (bool, error) {
diff --git a/packets/wtlogin/sso.go b/packets/wtlogin/sso.go
index df38cafa..d2a67df0 100644
--- a/packets/wtlogin/sso.go
+++ b/packets/wtlogin/sso.go
@@ -56,7 +56,7 @@ func ParseSSOHeader(raw, d2Key []byte) (*SSOHeader, error) {
 	var flag uint8
 	_ = binary.Read(buf, binary.BigEndian, &flag)
 	buf.Next(1)
-	uin := string(ParseLv(buf))
+	uin := utils.B2S(ParseLv(buf))
 
 	var dec []byte
 	if flag == 0 { // no encrypted
@@ -90,7 +90,7 @@ func ParseSSOFrame(buffer []byte, IsOicqBody bool) (*SSOPacket, error) {
 	sessionID := reader.ReadBytesWithLength("u32", true)
 
 	if retCode != 0 {
-		return NewSSOPacket(int(seq), int(retCode), extra, sessionID, "", make([]byte, 0)), nil
+		return NewSSOPacket(int(seq), int(retCode), extra, sessionID, "", nil), nil
 	}
 
 	compressType := reader.ReadU32()
diff --git a/packets/wtlogin/statusService.go b/packets/wtlogin/statusService.go
index 0daeeeb0..e3fbcf20 100644
--- a/packets/wtlogin/statusService.go
+++ b/packets/wtlogin/statusService.go
@@ -2,10 +2,11 @@ package wtlogin
 
 import (
 	"strings"
-
-	"github.com/LagrangeDev/LagrangeGo/packets/pb/system"
+	"unicode"
 
 	"github.com/LagrangeDev/LagrangeGo/info"
+	"github.com/LagrangeDev/LagrangeGo/packets/pb/system"
+	"github.com/LagrangeDev/LagrangeGo/utils"
 	"github.com/LagrangeDev/LagrangeGo/utils/proto"
 )
 
@@ -53,5 +54,9 @@ func ParseRegisterResponse(response []byte) bool {
 }
 
 func capitalize(s string) string {
-	return strings.ToUpper(string(s[0])) + strings.ToLower(s[1:])
+	news := make([]byte, len(s))
+	rs := []rune(s)
+	n := copy(news, string(unicode.ToUpper(rs[0])))
+	copy(news[n:], strings.ToLower(s[n:]))
+	return utils.B2S(news)
 }
diff --git a/utils/binary/builder.go b/utils/binary/builder.go
index eb28180f..ac8f0c7e 100644
--- a/utils/binary/builder.go
+++ b/utils/binary/builder.go
@@ -5,9 +5,14 @@ import (
 	"encoding/binary"
 	"math"
 
+	"github.com/LagrangeDev/LagrangeGo/utils"
 	"github.com/LagrangeDev/LagrangeGo/utils/crypto"
 )
 
+type PackType int
+
+const PackTypeNone PackType = -1
+
 type Builder struct {
 	buffer []byte
 	key    crypto.TEA
@@ -16,7 +21,7 @@ type Builder struct {
 
 func NewBuilder(key []byte) *Builder {
 	return &Builder{
-		buffer: make([]byte, 0),
+		buffer: make([]byte, 0, 64),
 		key:    crypto.NewTeaCipher(key),
 		usetea: len(key) == 16,
 	}
@@ -48,13 +53,14 @@ func (b *Builder) pack(v any) *Builder {
 	return b
 }
 
-func (b *Builder) Pack(typ int64) []byte {
-	if typ != -1 {
+func (b *Builder) Pack(typ PackType) []byte {
+	if typ != PackTypeNone {
 		// 或许这里是tlv
-		buf := new(bytes.Buffer)
-		_ = binary.Write(buf, binary.BigEndian, typ)                  // type
-		_ = binary.Write(buf, binary.BigEndian, int64(len(b.Data()))) // length
-		return append(buf.Bytes(), b.Data()...)                       // type + length + value
+		buf := make([]byte, b.Len()+4)
+		binary.BigEndian.PutUint16(buf[0:2], uint16(typ))           // type
+		binary.BigEndian.PutUint16(buf[2:4], uint16(len(b.Data()))) // length
+		copy(buf[4:], b.Data())                                     // type + length + value
+		return buf
 	}
 	return b.Data()
 }
@@ -69,10 +75,44 @@ func (b *Builder) WriteBool(v bool) *Builder {
 	return b
 }
 
-//func (b *Builder) WriteByte(v byte) *Builder {
-//	b.buffer = append(b.buffer, v)
-//	return b.pack(v)
-//}
+// WritePacketBytes default prefix = "", withPrefix = true
+func (b *Builder) WritePacketBytes(v []byte, prefix string, withPrefix bool) *Builder {
+	if withPrefix {
+		switch prefix {
+		case "":
+		case "u8":
+			b.WriteU8(uint8(len(v) + 1))
+		case "u16":
+			b.WriteU16(uint16(len(v) + 2))
+		case "u32":
+			b.WriteU32(uint32(len(v) + 4))
+		case "u64":
+			b.WriteU64(uint64(len(v) + 8))
+		default:
+			panic("Invaild prefix")
+		}
+	} else {
+		switch prefix {
+		case "":
+		case "u8":
+			b.WriteU8(uint8(len(v)))
+		case "u16":
+			b.WriteU16(uint16(len(v)))
+		case "u32":
+			b.WriteU32(uint32(len(v)))
+		case "u64":
+			b.WriteU64(uint64(len(v)))
+		default:
+			panic("Invaild prefix")
+		}
+	}
+	b.append(v)
+	return b
+}
+
+func (b *Builder) WritePacketString(s, prefix string, withPrefix bool) *Builder {
+	return b.WritePacketBytes(utils.S2B(s), prefix, withPrefix)
+}
 
 func (b *Builder) WriteBytes(v []byte, withLength bool) *Builder {
 	if withLength {
@@ -83,11 +123,11 @@ func (b *Builder) WriteBytes(v []byte, withLength bool) *Builder {
 }
 
 func (b *Builder) WriteString(v string) *Builder {
-	return b.WriteBytes([]byte(v), true)
+	return b.WriteBytes(utils.S2B(v), true)
 }
 
-func (b *Builder) WriteStruct(datas ...any) *Builder {
-	for _, data := range datas {
+func (b *Builder) WriteStruct(data ...any) *Builder {
+	for _, data := range data {
 		b.pack(data)
 	}
 	return b
@@ -132,13 +172,25 @@ func (b *Builder) WriteI64(v int64) *Builder {
 func (b *Builder) WriteFloat(v float32) *Builder {
 	return b.WriteU32(math.Float32bits(v))
 }
+
 func (b *Builder) WriteDouble(v float64) *Builder {
 	return b.WriteU64(math.Float64bits(v))
 }
-func (b *Builder) WriteTlv(tlvs [][]byte) *Builder {
+
+/*
+func (b *Builder) WriteTlv(tlvs ...[]byte) *Builder {
 	b.WriteU16(uint16(len(tlvs)))
 	for _, tlv := range tlvs {
 		b.WriteBytes(tlv, false)
 	}
 	return b
 }
+*/
+
+func (b *Builder) WritePacketTlv(tlvs ...[]byte) *Builder {
+	b.WriteU16(uint16(len(tlvs)))
+	for _, tlv := range tlvs {
+		b.WritePacketBytes(tlv, "", true)
+	}
+	return b
+}
diff --git a/utils/binary/builder_test.go b/utils/binary/builder_test.go
index b7d71204..7856574a 100644
--- a/utils/binary/builder_test.go
+++ b/utils/binary/builder_test.go
@@ -7,13 +7,13 @@ import (
 
 func TestBuilder(t *testing.T) {
 	r := []byte{1, 2, 3, 4, 5, 6, 7, 8, 9}
-	data := NewBuilder(nil).WriteBytes(r, true).Pack(-1)
+	data := NewBuilder(nil).WriteBytes(r, true).Pack(PackTypeNone)
 	fmt.Printf("%x\n", data)
 }
 
 func build() []byte {
 	r := []byte{1, 2, 3, 4, 5, 6, 7, 8, 9}
-	return NewBuilder(nil).WriteBytes(r, true).WriteBytes(r, true).Pack(-1)
+	return NewBuilder(nil).WriteBytes(r, true).WriteBytes(r, true).Pack(PackTypeNone)
 }
 
 func TestReader(t *testing.T) {
diff --git a/utils/binary/reader.go b/utils/binary/reader.go
index b30eb8f8..63f4cbc1 100644
--- a/utils/binary/reader.go
+++ b/utils/binary/reader.go
@@ -2,6 +2,8 @@ package binary
 
 import (
 	"encoding/binary"
+
+	"github.com/LagrangeDev/LagrangeGo/utils"
 )
 
 type Reader struct {
@@ -52,7 +54,7 @@ func (r *Reader) ReadBytes(length int) (v []byte) {
 }
 
 func (r *Reader) ReadString(length int) string {
-	return string(r.ReadBytes(length))
+	return utils.B2S(r.ReadBytes(length))
 }
 
 func (r *Reader) ReadBytesWithLength(prefix string, withPerfix bool) (v []byte) {
@@ -91,7 +93,7 @@ func (r *Reader) ReadBytesWithLength(prefix string, withPerfix bool) (v []byte)
 }
 
 func (r *Reader) ReadStringWithLength(prefix string, withPerfix bool) string {
-	return string(r.ReadBytesWithLength(prefix, withPerfix))
+	return utils.B2S(r.ReadBytesWithLength(prefix, withPerfix))
 }
 
 func (r *Reader) ReadTlv() (result map[int][]byte) {
diff --git a/utils/crypto/tea_test.go b/utils/crypto/tea_test.go
index e0c9c465..76d13c71 100644
--- a/utils/crypto/tea_test.go
+++ b/utils/crypto/tea_test.go
@@ -283,7 +283,7 @@ func xor(a, b []byte) []byte {
 	//_ = binary.Read(readerb, binary.BigEndian, &b1)
 	//_ = binary.Read(readerb, binary.BigEndian, &b2)
 
-	buf := make([]byte, 0)
+	buf := make([]byte, 0, 64)
 	buf = binary.BigEndian.AppendUint32(buf, (a1^b1)&uint32(OP))
 	buf = binary.BigEndian.AppendUint32(buf, (a2^b2)&uint32(OP))
 
@@ -331,7 +331,7 @@ func teaCode(v, k []byte) []byte {
 		v1 &= OP
 	}
 
-	buf := make([]byte, 0)
+	buf := make([]byte, 0, 64)
 	buf = binary.BigEndian.AppendUint32(buf, uint32(v0))
 	buf = binary.BigEndian.AppendUint32(buf, uint32(v1))
 
@@ -380,7 +380,7 @@ func teaDecipher(v, k []byte) []byte {
 		sum &= OP
 	}
 
-	buf := make([]byte, 0)
+	buf := make([]byte, 0, 64)
 	buf = binary.BigEndian.AppendUint32(buf, uint32(v0))
 	buf = binary.BigEndian.AppendUint32(buf, uint32(v1))
 
@@ -391,7 +391,7 @@ func preprocess(data []byte) []byte {
 	dataLen := len(data)
 	// 保证取余出来是正数
 	filln := ((8-(dataLen+2))%8+8)%8 + 2
-	fills := make([]byte, 0)
+	fills := make([]byte, 0, 64)
 	for i := 0; i < filln; i++ {
 		fills = append(fills, 220)
 	}
@@ -406,7 +406,7 @@ func encrypt(data, key []byte) []byte {
 	data = preprocess(data)
 	tr := make([]byte, 8)
 	to := make([]byte, 8)
-	result := make([]byte, 0)
+	result := make([]byte, 0, 64)
 	for i := 0; i < len(data); i += 8 {
 		o := xor(data[i:i+8], tr)
 		tr = xor(teaCode(o, key), to)
diff --git a/utils/log.go b/utils/log.go
index 49bfc04b..3479e5e6 100644
--- a/utils/log.go
+++ b/utils/log.go
@@ -62,7 +62,7 @@ func (f *ColoredFormatter) Format(entry *logrus.Entry) ([]byte, error) {
 			timestamp, levelColor, strings.ToUpper(entry.Level.String()), colorReset, 7-len(entry.Level.String()), "", entry.Data["prefix"], entry.Message)
 	}
 
-	return []byte(message), nil
+	return S2B(message), nil
 }
 
 func GetLogger(prefix string) *logrus.Entry {
diff --git a/utils/packet.go b/utils/packet.go
deleted file mode 100644
index e7cabc78..00000000
--- a/utils/packet.go
+++ /dev/null
@@ -1,169 +0,0 @@
-package utils
-
-import (
-	"bytes"
-	"encoding/binary"
-	"math"
-
-	"github.com/LagrangeDev/LagrangeGo/utils/crypto"
-)
-
-type PacketBuilder struct {
-	buffer []byte
-	key    crypto.TEA
-	usetea bool
-}
-
-func NewPacketBuilder(key []byte) *PacketBuilder {
-	return &PacketBuilder{
-		buffer: make([]byte, 0),
-		key:    crypto.NewTeaCipher(key),
-		usetea: len(key) == 16,
-	}
-}
-
-// WriteByte就是i8
-
-// WriteBytes 重写 默认参数 prefix = "", withPerfix = true
-func (b *PacketBuilder) WriteBytes(v []byte, prefix string, withPerfix bool) *PacketBuilder {
-	if withPerfix {
-		switch prefix {
-		case "":
-		case "u8":
-			b.WriteU8(uint8(len(v) + 1))
-		case "u16":
-			b.WriteU16(uint16(len(v) + 2))
-		case "u32":
-			b.WriteU32(uint32(len(v) + 4))
-		case "u64":
-			b.WriteU64(uint64(len(v) + 8))
-		default:
-			panic("Invaild prefix")
-		}
-	} else {
-		switch prefix {
-		case "":
-		case "u8":
-			b.WriteU8(uint8(len(v)))
-		case "u16":
-			b.WriteU16(uint16(len(v)))
-		case "u32":
-			b.WriteU32(uint32(len(v)))
-		case "u64":
-			b.WriteU64(uint64(len(v)))
-		default:
-			panic("Invaild prefix")
-		}
-	}
-	b.append(v)
-	return b
-}
-
-func (b *PacketBuilder) WriteString(s, prefix string, withPerfix bool) *PacketBuilder {
-	return b.WriteBytes([]byte(s), prefix, withPerfix)
-
-}
-
-func (b *PacketBuilder) Len() int {
-	return len(b.buffer)
-}
-
-func (b *PacketBuilder) append(v []byte) {
-	b.buffer = append(b.buffer, v...)
-}
-
-func (b *PacketBuilder) Buffer() []byte {
-	return b.buffer
-}
-
-func (b *PacketBuilder) Data() []byte {
-	if b.usetea {
-		return b.key.Encrypt(b.buffer)
-	}
-	return b.buffer
-}
-
-func (b *PacketBuilder) pack(v any) *PacketBuilder {
-	buf := new(bytes.Buffer)
-	_ = binary.Write(buf, binary.BigEndian, v)
-	b.append(buf.Bytes())
-	return b
-}
-
-func (b *PacketBuilder) Pack(typ int) []byte {
-	if typ != -1 {
-		// 或许这里是tlv
-		buf := make([]byte, 0)
-		buf = binary.BigEndian.AppendUint16(buf, uint16(typ))           // type
-		buf = binary.BigEndian.AppendUint16(buf, uint16(len(b.Data()))) // length
-		return append(buf, b.Data()...)                                 // type + length + value
-	}
-	return b.Data()
-}
-
-func (b *PacketBuilder) WriteBool(v bool) *PacketBuilder {
-	if v {
-		b.buffer = append(b.buffer, 1)
-	} else {
-		b.buffer = append(b.buffer, 0)
-	}
-
-	return b
-}
-
-func (b *PacketBuilder) WriteStruct(datas ...any) *PacketBuilder {
-	for _, data := range datas {
-		b.pack(data)
-	}
-	return b
-}
-
-func (b *PacketBuilder) WriteU8(v uint8) *PacketBuilder {
-	b.buffer = append(b.buffer, v)
-	return b
-}
-
-func (b *PacketBuilder) WriteU16(v uint16) *PacketBuilder {
-	b.buffer = binary.BigEndian.AppendUint16(b.buffer, v)
-	return b
-}
-
-func (b *PacketBuilder) WriteU32(v uint32) *PacketBuilder {
-	b.buffer = binary.BigEndian.AppendUint32(b.buffer, v)
-	return b
-}
-
-func (b *PacketBuilder) WriteU64(v uint64) *PacketBuilder {
-	b.buffer = binary.BigEndian.AppendUint64(b.buffer, v)
-	return b
-}
-
-func (b *PacketBuilder) WriteI8(v int8) *PacketBuilder {
-	return b.WriteU8(byte(v))
-}
-
-func (b *PacketBuilder) WriteI16(v int16) *PacketBuilder {
-	return b.WriteU16(uint16(v))
-}
-
-func (b *PacketBuilder) WriteI32(v int32) *PacketBuilder {
-	return b.WriteU32(uint32(v))
-}
-
-func (b *PacketBuilder) WriteI64(v int64) *PacketBuilder {
-	return b.WriteU64(uint64(v))
-}
-
-func (b *PacketBuilder) WriteFloat(v float32) *PacketBuilder {
-	return b.WriteU32(math.Float32bits(v))
-}
-func (b *PacketBuilder) WriteDouble(v float64) *PacketBuilder {
-	return b.WriteU64(math.Float64bits(v))
-}
-func (b *PacketBuilder) WriteTlv(tlvs [][]byte) *PacketBuilder {
-	b.WriteU16(uint16(len(tlvs)))
-	for _, tlv := range tlvs {
-		b.WriteBytes(tlv, "", true)
-	}
-	return b
-}
diff --git a/utils/string.go b/utils/string.go
new file mode 100644
index 00000000..4ff28c98
--- /dev/null
+++ b/utils/string.go
@@ -0,0 +1,22 @@
+package utils
+
+// from https://github.com/Mrs4s/MiraiGo/blob/master/utils/string.go
+
+import "unsafe"
+
+// B2S converts byte slice to a string without memory allocation.
+func B2S(b []byte) string {
+	size := len(b)
+	if size == 0 {
+		return ""
+	}
+	return unsafe.String(&b[0], size)
+}
+
+// S2B converts string to a byte slice without memory allocation.
+//
+// Note it may break if string and/or slice header will change
+// in the future go versions.
+func S2B(s string) (b []byte) {
+	return unsafe.Slice(unsafe.StringData(s), len(s))
+}